How do you approach patients who continue to experience pruritus and ongoing concern for persistent scabies despite having completed appropriate treatment?

Pruritus can not uncommonly continue in patients for 6 weeks or more after infestation is managed. High-dose antihistamines may be of some benefit. Consider if there is an ongoing untreated exposure that the patient has not thought of or cannot/will not share with you. Not all people infested with scabies have symptoms. "Appropriate" treatment may be in the eye of the beholder--did they actually follow instructions, repeat treatment, treat all close contacts, etc? Is resistance a possibility? If all of this has been thoroughly addressed, I assure the patient that their immune system is probably still "stirred up" and will calm back down with time. If persistent after 6 weeks and checking all of the above boxes, consider alternative diagnose...

Although pruritus may continue for 4-6 weeks after effective treatment of scabies, I would recommend doing a full skin exam to rule out any evidence of persistent infestation and certainly ask about exposure to close contacts who might still be infested.

If no evidence of infestation, I agree that antihistamines should help. I would also consider using topical steroids to any areas with significant evidence of persistent contact dermatitis. In sensitive areas could use topical calcineurin inhibitors as well. Daily warm baths followed by the application of emollients several times a day should also help.

@Dr. First Last had an awesome case like this treated with nemolizumab after failing many things.

Agree, scabies is contact dermatitis to mites. Expect only gradual improvement in the first month, with complete resolution of symptoms in 2-3 months. Anti-histamines don’t benefit contact dermatitis, but topical steroids will help after infestation is fully eradicated. I don’t see a role for emollients.

Given that scabies infestation/re-infestation is ruled out, I routinely treat teenagers and above complaining of persistent itch with IM Kenalog. Works wonders.

The combination of dilute bleach baths, mid-potency steroid ointment, and hydroxyzine works great. I counsel patients to use topical steroid Monday through Friday and take weekends off. Use dilute bleach solution in a spray bottle and/or pramoxine lotion stored in the refrigerator for breakthrough itch.

I tell patients they should experience an 80% improvement in pruritus immediately. If they experienced that, the residual 20% is nothing to worry about, and will improve with time as the skin recovers (and can use topical steroids and antihistamines to help).

After considering the aforementioned recommendations before, completion of permethrin/ivermectin/spinosad, IM Kenalog, sufficient time for hypersensitivity reaction to subside, etc., and still with lingering pruritus and notable concerns for continued infestation, Eurax (crotamiton) cream has recently re-entered the market.

If the skin is essentially without any notable lesions, and the patient has excessive concerns of "not being cured" as well as being unwilling to accept a clinical diagnosis of being clear, this will likely be my next step as a compromise solution.